Hierarchical few-layer fluorine-free Ti3C2TX (T = O, OH)/MoS2 hybrid for efficient electrocatalytic hydrogen evolution

As an eco-friendly and renewable energy source, hydrogen energy has attracted widespread attention. MoS2 nanomaterials are typical catalysts for the electrocatalytic hydrogen evolution reaction (HER), but their performances are limited by their poor conductivity and spontaneous agglomeration. Here, we prepared few-layer fluorine-free Ti3C2TX (T = O, OH) as a conductive substrate of MoS2 for HER catalysis, and the as-prepared hybrid catalyst exhibits high catalytic activity with a small overpotential of 139 mV at -10 mA cm(-2), a Tafel slope of 78 mV dec(-1), and a negligible decay after 3000 cycles at a scan rate of 100 mV s(-1) in an acidic solution. The excellent performance in HER activity can be attributed to the improved electrical conductivity, increased O active sites and optimized 2D mass-transport channels of the unique few-layer fluorine-free structure. Interestingly, the few-layer fluorine-free Ti3C2TX/MoS2 catalyst also performs well under neutral and alkaline conditions. This work demonstrates that few-layer fluorine-free Ti3C2TX (T = O, OH) can be used as an excellent conductive substrate to further improve the HER performances of other nanoscale electrocatalysts.